Papers by Keyword: Subwavelength Grating

Abstract: Nanostructures with top subwavelength hybrid dielectric gratings and metallic triangle back reflector in Si thin film solar cells (TFSCs) are introduced in this paper. Compared with the studied light-trapping structures with normal surface and bottom gratings, our optimized structure has a better performance. We can achieve above 26 percent average cell efficiency enhancement in contrast to the normal flat cells and about 40 percent increase with the transverse magnetic (TM) polarized irradiation only.

Abstract: Subwavelength gratings (SWGs) that consist of net-grid structure are designed as infrared reflectors in this paper. By rigorous coupled wave approach (RCWA) and finite difference time domain (FDTD) method, we simulate its reflectivity which can reach 99.98% at 1.55μm while maintaining reflectivity higher than 99% across the 1.47-1.59μm wavelength range. We introduce SWG reflectors as the bottom mirrors in resonant cavity enhanced photodetectors (RCE PDs). RCE PD's quantum efficiency is increased to 95.7% at 1.55μm and the device has a significant size reduction compared with only using DBR bottom mirror.